1. Field of the Invention
The current invention relates to a control system for a suspension provided on a vehicle such as an automobile, and in particular, relates to a control apparatus for a suspension provided with an actuator that applies a force to the vehicle wheels in a vertical direction.
2. Description of the Related Art
The suspension provided on a vehicle has the function of improving the ride comfort by absorbing shocks from the road surface with which the wheels are in contact, and generally, coil springs and shock absorbers that suppress the vibration of these coil springs are provided. When the spring rate of the coil spring provided on the suspension is made small, the ride comfort had a tendency to become smooth.
In contrast, when the spring rate is made small in order to make the ride comfort smooth, rolling occurs easily during the turning of the vehicle, pitching occurs easily during the acceleration and deceleration of the vehicle, and there is a tendency for controllability to decrease.
As explained above, because it is difficult to improve controllability and ride comfort of the vehicle together, generally the suspension of a vehicle is frequently set prioritizing either the ride comfort or prioritizing the controllability, depending on the characteristics of the vehicle.
In addition, stabilizers for increasing the roll resistance of the vehicle are conventionally known. In the case that the left and right wheels move in phase, the stabilizer does not act as a spring, but in the case that the left and right wheels move out of phase as happens during rolling, the stabilizer acts as a spring and thereby rolling is suppressed. Because the stabilizer acts as a spring only in the case that the left and right wheels are moving out of phase, rolling can be suppressed even if the spring rate of the coil panel is not made large.
When the spring rate of the coil spring is made small in order to improve the ride comfort, rolling can easily occur during turning, and thus it is necessary to make the reaction force produced by the stabilizer large by making the diameter of the stabilizer large or making the length of the part that generates the torsion short.
However, when the reaction force generated by the stabilizer is made large, in the case of driving straight on a road surface having irregular bumps and holes, the result is the same as having made the spring rate of the coil spring large, and there is the problem that the ride comfort is adversely influenced. In addition, the stabilizer can only suppress rolling, and it is not possible to attain the effect of suppressing pitching and bouncing.
In consideration of the problems described above, it is an object of the current invention to provide a suspension control apparatus that executes control of an actuator that applies a force to the vehicle wheels in the vertical direction depending on the state of travel of the vehicle, and at the same time, carries out electrical generation by using the energy of the vertical movement of the vehicle wheels, and uses the obtained electrical energy to drive the actuator.